It seems that Imia’s uncle and the old man from the weapon shop were fellow disciples under the same craftsman when they were younger.
“Even if I say that….I dropped out in the middle. There were a lot of troubles at home and we had to raise Imia and the other children.” (Imia’s uncle)
“The management was completely screwed up back then.” (Oyaji)
“Despite being craftsmen?” (Naofumi)